Inter-patient and intra-patient variations in the baseline values of the tapping test were studied in 22 patients with Parkinson's disease using the unequal sample sizes model II one-way analysis of variance (ANOVA). The results show that intra-patient variation accounts for about 15.8% of the total variation, inter-patient variation accounts for about 84.2% of the total variation, and the coefficient of variation (CV) in intra-patient variation is 15.8%. The results suggest that at least two or three baseline tapping tests are needed to determine the baseline value of the tapping tes